Epo Connection; Backfeed Protection - CyberPower OLS3S15KE User Manual

4.7. EPO Connection

EPO (Emergency power off): when the emergency occurs, such as the failure of load,
the UPS can cut off the output at once by operating the EPO port manually.
The connection
Normally the EPO connector is closed with a wire on the rear panel (Fig.4-6), which is
supplied in the accessory. Once the connector is open, the UPS would stop the
output and enter EPO status (Fig.4-5).
Fig.4-5 Enable the EPO status
To recover to normal status, first EPO connector should be closed, and enter LCD
menu (illustrated in the chapter of 5.3) to clear EPO status, then UPS would stop
alarm and recover to Bypass model. And UPS needs be turned on by manual
operation.

4.8. Backfeed Protection

On customers side an additional external isolation device (magnetic contactor, MC or
minimum voltage tripping device) must be provided as shown in the following diagram.
The isolation device must be able to carry the UPS input current (see resp. table of
basic UPS operating instructions).
The isolation device has to be installed in the bypass source path.
MAIN 2:
L/N
MAIN 1:
L1
L2
L3
N
Fig.4-7 Typical external isolating device installation
AC Contactor
Coil Remotes Switch
Fig.4-6 Disable the EPO status
UPS
MAIN BOARD
16
Output/L
Output/N